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Файл:Английский для студентов-энергетиков. Учебное пособие
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Wires connecting the components of various installations may be insulated.
They may also be used without insulation. Since in short lengths of wire power loss is
exceedingly low one can ignore it. In long wires (longer than 10 m), power loss
cannot be ignored since it is rather high. Power loss in a line should not exceed a
definite value. If this value is exceeded the line becomes inefficient.
One should know that the efficiency of a line is not constant it may change.
The value of the line efficiency depends on the load: the greater the load the lower is
the line efficiency. At voltage losses of 2 to 5 per cent the efficiency of a line is 98-95
per cent. Protecting devices, fuses and relays are used to protect the circuit against
overcurrents and short-circuits.
Transmission Lines
A power system is an interconnection of electric power stations by high voltage
power transmission lines. Nowadays the electricity is transmitted over long distances
and the length of transmitting power lines varies from area to area.
A wire system is termed a power line in case it has no parallel branches and a
power network in case it has parallel branches.
According to their functions, power lines and networks are subdivided into
transmission and distribution lines.
Transmission lines serve to deliver power from a station to distribution centres.
Distribution lines deliver power from distribution centres to the loads.
Lines are also classed into: 1) overhead; 2) indoor; 3) cable (underground).
Overhead lines include line conductors, insulators, and supports. The
conductors are connected to the insulators, and these are connected to the supports.
The greater the resistance, the higher are the heating losses in the conducting wires.
In order to reduce the losses, a step-down transformer can be used.
Indoor lines include conductors, cords, and buses. The conductor may include
one wire or a combination of wires not insulated from one another. They deliver
electric current to the consumers.
As to underground lines, they are used in city areas. It demonstrates the higher
technology in developed countries for fire prevention and to make the power lines
less vulnerable to outages during high wind thunderstorms or heavy snow or ice
storms.
Accordingly, they are used in cities and towns, and in the areas of industrial
enterprises» [10].
Task 3. Answer the following questions:
1) What are the main components of any circuit?
2) What are the most common power sources?
3) Do electric generators convert chemical energy into electric energy?
4) What do loads include?
5) Do motors convert electric energy into mechanical energy?
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6) Is electric power delivered from power sources to loads by electric
1) An
underground
transmission is
a) a specialized cable or other structure designed to
conduct electromagnetic waves in a contained manner;
b) the final stage in the delivery of electric power; it carries
electricity from the transmission system to individual
consumers.
c) a network consisting of a closed loop, giving a return path
for the current.
d) a device connected to the output of a circuit
e) (redirect from Power grid) electric power electrical
substations for stepping electrical voltage up for
transmission, or down for distribution high voltage
transmission lines
distribution to transmit electrical energy across large
distances. It consists of one or more uninsulated electrical
cables (commonly multiples of three for three-phase power)
suspended by towers or poles.
electrical power or telecommunications, with underground
cables.
2) An overhead
power line is
3) Electrical grid
4)An electrical
circuit is
5)Electric
power distribution
is
6) a transmission
line is
wires?
7) Do electric circuits use different types of switches, protection devices
(relays and fuses), and meters?
Task 4. Match the following words from the text with their definitions:
Task 5. Complete the sentences using the following words or phrases from the
text in the correct form: transformer; wires; insulators; centres; lines; network;
interconnection.
1. A power system is an… of electric power stations by high voltage power
transmission lines.
2. A wire system is termed a power line in case it has no parallel branches, and a
power …in case it has parallel branches.
3. According to their functions, power lines and networks are subdivided into
transmission and distribution….
4. Distribution lines deliver power from distribution… to the loads.
5. The conductors are connected to the…, and these are connected to the supports.
6. The greater the resistance, the higher are the heating losses in the conducting
…
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7. In order to reduce the losses, a step-down …can be used.
Task 6. Read the statements and decide whether you agree or disagree with
them. Say to what extent you agree or disagree and try to give your arguments:
-agree strongly
-agree
-not sure
-disagree
-disagree strongly
1) Wires are used to deliver electric power and to disconnect different
components of electrical installations.
2) Conductors used for electric wiring are commonly produced of copper and
aluminium.
3) Aluminium is not widely used nowadays due to its high cost.
4) Wires connecting the components of various installations may be insulated.
5) Power loss in a line should not exceed a definite value.
6) One should know that the efficiency of a line is constant.
7) The value of the line efficiency depends on the load: the greater the load the
higer is the line efficiency.
8) Protecting devices, fuses and relays are used to protect the circuit against
overcurrents and short-circuits.
Task 7. Read the following descriptions and decide which one is about
1) an underground line
2) an indoor line
3) an overhead power line
4)
1. ………..is used to transmit electrical energy across large distances. It
consists of one or more uninsulated electrical cables (commonly multiples of three
for three-phase power) suspended by towers or poles.
2. ………is used to deliver electric current to the consumers.
3. ...…… is used in city areas for fire prevention and to make the power lines
less vulnerable to outages during high wind thunderstorms, or heavy snow, or ice
storms.
Task 8. Talk about the differences between transmission and distribution lines.
73
1) a nameplate
2) machine ratings
3) to bear
4) the output power
5) the voltage
6) the rated current
7) the starting current
8) the power factor
9) the efficiency
10) the rated torque
a) крутящий момент
b) КПД
c) коэффициент мощности
d) пусковой ток
e) номинальный ток
f) напряжение
g) выходная мощность
h) указывать
i) номинальные параметры машины
j) паспортная табличка
1) strength of current
2) current of 100 mA is lethal
3) earthing system
4) attending personnel
5) parts that are normally dead
6) contacts with live conductors
7) live parts of installations
8 ) connecting to ground
9) earthing electrodes
10) insulation resistance
a) изоляционное сопротивление
b) заземляющие электроды
c) заземление
d) токопроводящие части
установок
e) контакты с токопроводящими
проводниками (с проводами)
f) части, которые обычно
обесточены
g) обслуживающий персонал
h) система заземления
i) ток в 100 мA смертелен
j) сила тока
Task 1. Match the following English words and phrases from text G with their
Russian equivalents:
Unit 7
ELECTRIC MOTORS
Task 2. Match the following English word combinations from text G with their
Russian equivalents:
energy. The main part of a motor is a coil or armature. The armature is placed
Task 3. Read and translate text G:
«Motors are used for converting different forms of energy into mechanical
Electric Motors
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between the poles of a powerful magnet. When a motor is put into operation current
starts flowing through the coil (armature) and the armature begins to rotate.
Electric motors are used practically in every branch of industry, transport, and
agriculture. Naturally, they are produced in many different forms. They are used in
industrial plants, and operate under different conditions.
Each motor is supplied with a nameplate which bears machine ratings: output
power, voltage, the rated current, the starting current, the power factor, the efficiency,
and the rated torque.
These motor ratings should be taken into consideration since they are necessary
for the users. the length of motors’ service life depends On them: normally it is equal
to about 10 years, (if the operating conditions are normal). Naturally, under abnormal
conditions the service life becomes much shorter: motors operate poorly and may
have different faults.
Safety Earthing System. Electric Shock
The strength of current depends on both the voltage and the resistance in a
circuit. A current of 50 mA is dangerous for a man and a current of 100 mA and
higher is lethal.
Earthing system serves to protect attending personnel from electric shocks
when voltage appears on parts that are normally dead. The risk of an electric shock
decreases with decreasing voltage. In wet and hot atmosphere, the risk of electric
shock increases. Safe voltage for circuits are used in dry atmosphere (under 36 V).
When the power is on, contacts with live conductors are dangerous for life. Thus,
measures are taken to protect attending personnel from contacts with live parts of
installations under voltage.
The danger of an electric shock disappears provided the metal parts of
installations under voltage are connected with ground by means of safety earthing.
Connecting to ground is made by means of earthing electrodes which are connected
directly with ground.
The insulation resistance of any installation should be regularly controlled by
means of measuring devices. The faulty parts should be detected, eliminated, and
replaced by new ones» [7].
Task 4. Answer the following questions:
1) Are motors used for converting different forms of energy into mechanical
energy?
2) What are the main parts of a motor?
3) Where is the armature placed?
4) Where are electric motors used?
5) Are they produced in many different forms?
6) Is each motor supplied with a nameplate which bears machine ratings?
7) Under abnormal conditions the service life becomes much shorter, doesn’t it?
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Task 5 Complete the sentences using the following words or phrases from the
text in the correct form: devices; electrodes; installations atmosphere; voltage;
system; strength.
1) The …of current depends on both the voltage and the resistance in a circuit.
2) Earthing … serves to protect attending personnel from electric shocks when
voltage appears on parts, that are normally dead.
3) The risk of an electric shock decreases with decreasing….
4) Safe voltage for circuits are used in dry … (under 36 V).
5) Thus, measures are taken to protect attending personnel from contacts with
live parts of …under voltage.
6) Connecting to ground is made by means of earthing …which are connected
directly with ground.
7) The insulation resistance of any installation should be regularly controlled by
means of measuring….
Task 6. Read the statements and decide whether you agree or disagree with
them. Say to what extent you agree or disagree and try to give your arguments:
-agree strongly
-agree
-not sure
-disagree
-disagree strongly
1) Motors are used for converting different forms of energy into kinetic energy.
2) The main part of a motor is a coil or armature.
3) The armature is placed between the poles of a powerful magnet.
4) Naturally, under abnormal conditions the service life becomes much longer.
5) The strength of current depends on both the voltage and the resistance in a circuit.
6) The risk of an electric shock increases with decreasing voltage.
7) In wet and hot atmosphere, the risk of electric shock increases.
Task 7. Talk about the risk of an electric shock and its prevention.
Part 4
Unit 1
SOURCES OF ENERGY
Task 1. Match the following English words and phrases from text A with their
Russian equivalents:
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1) various
2) waterfall
3) sources of current
4) generator
5) to turn into
6) above-mentioned
7) electric current
8) quantity
9) civilization
10) need of energy
a) электрический ток
b) превратиться в
c) генератор
d) количество
e) водопад
f) разнообразные
g) вышеупомянутый
h) цивилизация
i) источники
j) потребность в энергии
Task 2. Read and translate text A:
Energy
«In the language of science energy is the ability to do work. There are various
forms of energy, such as heat, mechanical, electrical, chemical, atomic and so on.
One might also mention the two kinds of mechanical energy–potential and kinetic,
potential energy being the energy of position while kinetic energy is the energy of
motion.
It is well known that one form of energy can be changed into another. A
waterfall may serve as an example. Water falling from its raised position, energy
changes from potential to kinetic energy. The energy of falling water is generally
used to turn the turbines of hydroelectric stations. The turbines in their turn drive the
electric generators, the latter producing electric energy. Thus, the mechanical energy
of falling water is turned into electric energy. The electric energy, in its turn, may be
transformed into any other necessary form.
When an object loses its potential energy, that energy is turned into kinetic
energy. Thus, in the above-mentioned example when water is falling from its raised
position, it certainly loses its potential energy, that energy changing into kinetic
energy.
the electric current. Generally speaking, the sources of energy usually employed to
produce current are either chemical as in the battery, or mechanical, as in the
We have already seen that energy of some kind must be employed to generate
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electromagnetic generator. Chemical sources of current having a limited application,
1) energy
2) current
3)solar
energy
4) decreasing
5) increasing
6) scientist
7) furnace
8) battery
a) energy derived from the sun in the form of solar radiation
b) becoming less or fewer; diminishing
c) an expert in science, especially one of the physical or
natural sciences.
d) electricity
e) any source of usable power, as fossil fuel, electricity, or
solar radiation.
f) growing larger or greater; enlarging; augmenting.
g) a structure or apparatus in which heat may be generated, as
the great quantities of electric energy generated today come from various forms of
mechanical energy.
The rising standards of modern civilization and growing industrial application
of the electric current result in an increasing need of energy. Every year we need
more and more energy. We need it to do a lot of useful things that are done by
electricity.
However, the energy sources of the world are decreasing while the energy
needs of the world are increasing. These needs will continue to grow as more motors
and melted metals are used in industry and more electric current is employed in
everyday life. As a result, it is necessary to find new sources of energy.
The sun is an unlimited source of energy. However, at present, only a little part
of solar energy is being used directly. How can we employ solar energy directly to
produce useful energy? This is a question which has interested scientists and
inventors for a long time. Lavoisier and other great scientists of the past melted
metals with the help of solar furnaces. Today, solar furnaces illustrate just one of the
numerous ways to harness the sun. Using semiconductors, scientists, for example,
have transformed solar energy into electric energy» [9].
Task 3. Answer the following questions:
1. What is energy?
2. What are the forms of energy?
3. How many types of mechanical energy can you mention?
4. One form of energy can be changed into another, can’t it?
5. What is the function of turbines?
6. Why do we need more and more energy every year?
7. Why do you think the energy sources of the world are decreasing?
8. What sources of energy are usually employed to produce current?
9. What do solar furnaces illustrate today?
10. How is solar energy transformed into electric energy?
Task 4. Match the following words from the text with their definitions:
78
9) motor
for heating houses,
g) a comparatively small and powerful engine, especially an
internal-combustion engine
h) a combination of two or more cells electrically connected
to work together to produce electric energy.
1) renewable
2) non-renewable
3) energy storage
4) fossil fuels
5) smart grid
6) energy storage
a) не возобновляемая
b) интеллектуальная сеть
c) накопление энергии
d) возобновляемая
f) энергетический запас
g) ископаемое топливо
Task 5. Read the following descriptions and decide which one is about
a) kinetic energy
b) potential energy
c) solar energy
1. …… is the energy of a body or a system with respect to the motion of the
body or of the particles in the system
2. ……… is the energy derived from the sun in the form of solar radiation.
3……….is the energy of a body or a system with respect to the position of the
body or the arrangement of the particles of the system.
Task 6. It is said that the energy sources of the world are decreasing. Can
you explain what it means?
Task 7. Look at the following words from the text. What parts of speech are
they? How are they formed? Can you think of more examples?
mechanical
electrical chemical
atomic
potential
kinetic
Task 8. Talk about the differences between potential and kinetic energy.
Unit 2
INTEGRATION INTO THE ENERGY SYSTEM
Task 1. Match the following English words and phrases from text B with their
Russian equivalents:
79
Task 2. Read and translate the text:
«Renewable energy production from some sources such as wind and solar is
more variable and more geographically spread than technology based on fossil fuels
and nuclear. While integrating it into the wider energy system is feasible, it does lead
to some additional challenges.
In order for the energy system to remain stable, a set of measurements can be
taken. Implementation of energy storage, using a wide variety of renewable energy
technologies, and implementing a smart grid in which energy is automatically used at
the moment it is produced can reduce risks and costs of renewable energy
implementation. In some locations, individual households can opt to purchase
renewable energy through a consumer green energy program.
Electrical energy storage
Electrical energy storage is a collection of methods used to store electrical
energy. Electrical energy is stored during times when production (especially from
intermittent sources such as wind power, tidal power, solar power) exceeds
consumption, and returned to the grid when production falls below consumption.
Pumped-storage hydroelectricity accounts for more than 90% of all grid power
storage. Costs of lithium-ion batteries are dropping rapidly, and are increasingly
being deployed grid ancillary services and for domestic storage» [11].
Task 3. Answer the following questions:
1. What are the sources of production of renewable energy?
2. What can reduce risks and costs of renewable energy implementation?
3. What is electrical energy storage?
4. Do you know where individual households can opt to purchase renewable
energy through a consumer green energy program?
5. Why can a set of measurements be taken?
6. How much does pumped-storage hydroelectricity account?
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